SA’s mystery COVID-19 source revealed
Details surrounding the initial source of Adelaide's coronavirus cluster have been revealed as South Australia races against the clock to contain its latest COVID-19 outbreak.
Genomic testing has found the mystery source is a traveller who came into Adelaide on November 2 and tested positive the next day.
South Australia's chief health officer Professor Nicola Spurrier confirmed testing of the strain contracted by the first confirmed case of the Parafield cluster - an 80-year-old woman - identified the link with the person who came from abroad.
"We've tested her strain and we've linked it to somebody in the medi-hotel where her daughter worked," Professor Spurrier said.
"The person who was the traveller arrived in South Australia on 2 November and was tested on 3 November. So, prior to this, prior to 2 November, we did not have COVID in the state, but that's when it was introduced, this particular strain."
It comes as dramatic scenes unfolded Tuesday afternoon at Peppers Adelaide as quarantining guests at the medi-hotel screamed from their balconies, devastated they won't be able to leave, despite testing negative for coronavirus.
Meanwhile a leading Australian epidemiologist has warned Australians of the seriously infectious rate of COVID-19 and that if you come close enough to be exposed to it, "you're going to get it".
She said the real question for South Australians was how much time or "circulation" the virus had in the community in the time between the initial infection occurring and the first case arising in the 80-year-old woman at the end of last week.
Dr Emma Miller, a senior lecturer and epidemiologist from Flinders University who is based in Adelaide, told news.com.au that "everyone that comes in contact with this is susceptible" and that "if you come in contact with it and are exposed, you're going to get it."
She says South Australia is "very much on the precipice" and there is potential the state could see a second wave if the virus continues to spread.
Burnet Institute epidemiologist Professor Michael O'Toole echoed those comments, describing South Australia's outbreak as "kind of a microcosm of the beginning of the second wave in Victoria".
Dr Miller said she understood the idea of quarantine is "scary" but defended public health officials saying the rules were in force due to an "abundance of caution".
SA Health says there are now 20 confirmed cases linked to the Parafield coronavirus cluster and another 14 suspected cases that are showing symptoms and are close contacts of the already confirmed cases. They're either waiting for test results or have had a negative test result but are being retested.
"These are people who are particularly younger children who have tested negative but may have symptoms and have a parent that's positive," Professor Spurrier said.
"We're being extra, extra cautious".
SA recorded five new cases Tuesday, one an aged care worker and three family members of a security guard who worked the medi-hotel. The fifth case has been confirmed and the person is being interviewed while the ages of the cases range from their teens to their 50s.
"That's what the problem with this virus is," Dr Miller told news.com.au.
"This is the problem with any pandemic virus, you're talking about a novel virus which nobody has any resistance whatsoever.
"If you come in any meaningful way in contact with this virus and you don't have any innate immunity or haven't had it before, you're going to get this virus.
"There are 7 billion people on this planet and that's the problem, that's why we have a pandemic.
"The fact that we're all susceptible means that, while most with have a mild form of the disease, in absolute terms we're getting a lot of deaths and a lot of serious complications as a result."
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The cluster has triggered closures and isolation warnings across the state with five schools shutting down for deep cleaning.
More than a dozen schools, hotels, cafes and supermarkets have been linked to the cluster and 4000 people who are considered close contacts of the confirmed case are now in quarantine.
Health investigators earlier said a cleaner became infected via surface at the quarantine hotel then passed the virus onto two security guards and members of their extended family.
"We've known this about all the respiratory viruses," Dr Miller said.
"In fact most colds can be spread by fomites - the bug which is left on surfaces - and people touch those surfaces and then touch their eyes normally. It's a very common way of spread."
"We know how long this particular virus lives on surfaces and we know that it doesn't stay long on paper, cotton, but it does stay for a long time on materials like steel and plastic.
"Most respiratory infections in cold and flu season can actually be spread that way, this is why we tell people to wash their hands, to not touch their eyes, that's the easiest way not to spread respiratory infections.
As residents fear the worst, more than 6000 tests were expected to be completed on Tuesday and the state is on track for record testing numbers for a single day.
Yet Dr Miller says there's no need to panic just yet and was confident the state health department was "swinging into action".
"It sounds scary, but it's actually not yet that bad," she reassured.
"The new cases that have arisen are mainly attached to that original cluster. We're still not seeing any large scale community involvement."
Officials are racing against the clock to contain the spread of the virus in the state, while the South Australian premier Steven Marshall on Monday issued advice to residents to wear masks on public transport and where it's not possible to socially distance.
Mr Marshall told residents his "unequivocal priority" was keeping the people of the state safe and strong but noted "time is now of the essence and we must act swiftly and decisively".
"We cannot wait to see how bad this gets," he said, as the cluster rose to up to 19 overnight, with at least 15 cases from the one family.
Dr Miller theorised that while a vaccine is the most likely source of the pandemic's end, there was a possibility history could repeat itself and that the virus could die out naturally.
"It's really difficult to tell because when you think about things like the Spanish flu at the beginning of the last century, that actually died out with no vaccine, likely due to mutation into a less lethal form" she said.
"For various reasons that happens with both bacterial epidemics as well, for instance, once we had the bubonic plague raging around the world, and cholera, they didn't die out because of a vaccine, it just` died out.
Dr Miller said there have been lots of conversations and suggestions that could be due to herd immunity but it didn't touch enough of the world to be able to explain it, although quarantining probably also helped.
"Sometimes these things just die out. In fact the nearest relative of the current virus is SARS and MERS and they just died out as well."
She said the reason that scientists are so far ahead with vaccine development is because they "had already done all that work trying for vaccinations for the original SARS".
"We could come up with a vaccine, it's very likely it will happen, but probably other things will intervene," she said.
"I don't know whether this virus will die out naturally as have other pandemics have in previous generations or whether it's going to disappear because we are going to have a vaccine, but eventually things will settle down.
"But what I know is that other ones will emerge".
Originally published as SA's mystery COVID-19 source revealed